There are many situations where there is a medical indication to insert a catheter or a tube into a body cavity. For example, with regard to the abdominal cavity, a catheter or tube may be required for various conditions and medical indications, such as peritoneal dialysis, a ventriculo-peritoneal shunt, diagnostic peritoneal lavage, and paracentesis, among other conditions. The insertion of a catheter or tube may also be required in the thoracic cavity for treating various conditions therein, such as pneumothorax, pleural effusion, and hemothorax, among other conditions.
Laparoscopic surgery has replaced open conventional surgery for many invasive procedures because it reduces morbidity, pain, and hemorrhaging due to smaller incisions, and results in shorter hospitalizations. Laparoscopy uses a laparoscope (a thin, lighted tube that includes a camera) put through a small incision in the abdomen created by a needle. The surgeon can view the abdominal organs or female reproductive organs using a camera passed through the tube. Laparoscopy can be used to find cysts, adhesions, fibroids, infection, and other ailments. Tissue samples can also be taken for biopsy through the laparoscope. The laparoscope allows doctors to perform both minor and complex surgeries with a few small cuts in the abdomen. However, conventional laparoscopic techniques pose risks of damaging organs and other tissues within the peritoneal or other cavities, and thus have substantial drawbacks.
The two most common techniques used to gain entry into the peritoneal cavity during laparoscopic general surgery are the blind needle/trocar insertion and open trocar placement under direct visualization. Once entry into the peritoneal cavity has been achieved, gas insufflation is used to establish pneumoperitoneum. The advantages of establishing a pneumoperitoneum include increased distance between the abdominal wall and viscera/vessels and increased resistance of the abdominal wall, allowing the surgeon to establish a surgical cannula (or channel) in the abdominal wall and insert instruments through the cannula without collapsing the abdominal wall on the internal organs and tissues.
Complications associated with operative laparoscopy usually arise from injury to internal structures during abdominal entry. The use of conventional blind needle access can create substantial risks of injury for laparoscopy patients. The drawbacks of establishing pneumoperitoneum also include the risk of bowel or vascular injury and preperitoneal placement of the catheter. The incidence of bowel and vascular injuries is relatively low (about less than 1%). However, a major vascular injury or unrecognized bowel injury carries significant morbidity and mortality rates. Preperitoneal placement of the needle allows for extraperitoneal insufflation of gas which can lead to subcutaneous emphysema and increased distance between the skin and peritoneal cavity making eventual percutaneous placement much more difficult. This may require abandonment of the laparoscopic procedure all together. Gas embolus may occur if a blood vessel is punctured by the needle and the CO2 gas pumped through the needle during insufflation is introduced into the blood vessel. Although rare, a gas embolus is potentially fatal. As a further example, existing techniques for diagnostic peritoneal lavage require a long incision along the linea alba, which results in significant pain and is practically impossible to perform with local anesthesia alone. Improvements in the instruments and techniques used to access the abdominal cavity are needed.
There are also drawbacks to the existing techniques for accessing the thoracic cavity (e.g., to drain fluid in the case of pleural effusion, empyema, hemothorax, etc.). Existing techniques include: 1—blindly accessing the cavity through the thoracic wall with a trocar or cannula, which can result in injury to the tissues within the cavity. Additionally, conventional techniques do not offer minimally invasive systems or methods for quickly accessing body cavities in emergency situations without significant risk of injury. Furthermore, the only acceptable method for evacuating the thorax emergently is by open technique which is associated with significant risks of bleeding, internal organ injury including injury to the lungs, heart, liver, and other organs and tissues. The open surgical techniques are currently used in procedures for accessing the thoracic cavity because all the current minimally invasive techniques require accompanying imaging when used in the thoracic cavity, which is usually not available in emergent situations. Radiographic guided methods may minimize the trauma to the tissue, but such techniques require special expertise, patient transfer to a cath lab or IR suite and necessitate the use of additional costly imaging, which may not be available.
Thus, conventional techniques for accessing and draining fluid from body cavities have high risk of injury due to blind needle insertion and/or require systemic anesthesia. As mentioned above, catheter insertion is currently accomplished by one of two main methods:                1. Open or endoscopic surgical technique, which are associated with can result in unnecessary tissue trauma and pain, an increased time for healing, higher risk of infection and bleeding, and the need for general anesthesia; and        2. Radiographic guided methods that may minimize the trauma to the tissue, but that require special expertise, patient transfer to a cath lab or IR suite, and the use of additional costly imaging, that may not be available.        
Therefore, there is a need for new, safer techniques that can be performed more quickly and efficiently at the bedside without the absolute need for systemic anesthesia. It is thus desirable to provide improved catheter/device delivery systems and methods for accessing the peritoneal cavity, the thoracic cavity, and other cavities in the body of humans or animals that reduce the risk of injury. The present invention provides such a catheter/device delivery system and methods of using the same, which include improvements over related conventional technologies and provide desirable results as described below.